# Math and Equations¶

Jupyter Book uses MathJax for typesetting math in your book. This allows you to have LaTeX-style mathematics in your online content. This page shows you a few ways to control this.

For more information about equation numbering, see the MathJax equation numbering documentation.

## In-line math¶

To insert in-line math use the `$`

symbol within a Markdown cell.
For example, the text `$this_{is}^{inline}$`

will produce: \(this_{is}^{inline}\).

## Math blocks¶

You can also include math blocks for separate equations. This allows you to focus attention
on more complex or longer equations, as well as link to them in your pages. To use a block
equation, wrap the equation in either `$$`

or `\begin`

statements.

For example,

```
\begin{equation}
\int_0^\infty \frac{x^3}{e^x-1}\,dx = \frac{\pi^4}{15}
\end{equation}
```

results in

\begin{equation} \int_0^\infty \frac{x^3}{e^x-1},dx = \frac{\pi^4}{15} \end{equation}

and

```
$$
\int_0^\infty \frac{x^3}{e^x-1}\,dx = \frac{\pi^4}{15}
$$
```

results in

### Numbering equations¶

If you’d like to number equations so that you can refer to them later, use the **math directive**.
It looks like this:

```
```{math}
:label: my_label
my_math
```
```

For example, the following code:

```
```{math}
:label: my_label
w_{t+1} = (1 + r_{t+1}) s(w_t) + y_{t+1}
```
```

Will generate this:

Note

Labels cannot start with an integer, or they won’t be able to be referenced and
will throw a warning message if referenced. For example, `:label: 1`

and `:label: 1eq`

cannot
be referenced.